N-Heterocyclic Carbene-Catalyzed Formal Intramolecular [3 + 2] Annulations of Cyclohexadienone-Tethered Ynals.

A formal [3 + 2] annulation of cyclohexadienone-tethered ynals is enabled by an N-heterocyclic carbene (NHC) catalyst, affording a tricyclo[6.2.1.

Material Design of Ultra-Thin InN/GaN Superlattices for a Long-Wavelength Light Emission.

GaN heterostructure is a promising material for next-generation optoelectronic devices, and Indium gallium nitride (InGaN) has been widely used in ultraviolet and blue light emission. However, its applied potential for longer wavelengths still requires exploration. In this work, the ultra-thin InN/GaN superlattices (SL) were designed for long-wavelength light emission and investigated by first-principles simulations.

Theoretical Analysis and Numerical Simulation of the Wear of the Sealing Substrate of a High-Pressure, High-Frequency Opening and Closing Hydrogen Ball Valve.

High-pressure valves are an essential infrastructure for hydrogen refueling stations, and the issue of safety and reliability of their operation affects the efficiency of the entire hydrogen delivery system. Hydrogen ball valves are subjected to high-frequency, rapid reciprocating opening and closing for a long time, and the sealing surface between the valve seat and the ball has an uneven wear distribution problem. In this paper, a theoretical derivation of the seat wear volume and wear depth during the hydrogen ball valve adhesive wear process is presented, and a simulation model based on transient dynamics theory is established to carry out a nonlinear finite element analysis of the dynamic contact and frictional wear of the sealing structure during the opening and closing process of the hydrogen ball valve.

A Highly Enantioselective Homoenolate Michael Addition/Esterification Sequence of Cyclohexadienone-Tethered Enals via NHC Catalysis.

Reported here is a highly enantioselective homoenolate Michael addition/esterification sequence of cyclohexadienone-tethered enals via N-heterocyclic carbene (NHC) catalysis, affording the enantiopure -hydrobenzofurans, -hydroindoles, and -hydroindenes. The NHC catalyst bearing a nitro group greatly enhances the stereocontrol, and a bulky -aryl substituent of the triazolium salt in the catalyst is helpful for inhibiting the further aldol condensation after homoenolate Michael addition. The utility of this protocol is highlighted by a gram-scale experiment and versatile downstream transformations.

High-Efficient Spin Injection in GaN at Room Temperature Through A Van der Waals Tunnelling Barrier.

Achieving high-efficient spin injection in semiconductors is critical for developing spintronic devices. Although a tunnel spin injector is typically used, the construction of a high-quality tunnel barrier remains a significant challenge due to the large lattice mismatch between oxides and semiconductors. In this work, van der Waals h-BN films with the atomically flat interface were engaged as the tunnel barrier to achieve high spin polarization in GaN, and the spin injection and transport in GaN were investigated systematically.

Cylindrical Al Nano-Dimer Induced Polarization in Deep UV Region.

The polarization properties of asymmetric plasmonic nanostructures originating from optical anisotropy show great application prospects in many fields, such as display, sensing, filtering, and detection. Here, we report the realization of polarization control in the deep ultraviolet (UV) region using Al nano-dimer structures. The simulation results indicated that the polarization effect was generated by the modulation of inter-coupling between the quadrupole plasmon resonances of the asymmetric dimer.

Molecular epidemiology of hepatitis B virus genotypes and subgenotypes in ethnic minority populations, Yunnan province, China.

The aim of our study was to determine the distribution of hepatitis B virus (HBV) genotypes and subgenotypes in ethnic minorities in Yunnan province to provide evidence supporting the theoretical basis for hepatitis B prevention and control. We obtained serum samples and demographic data from 765 individuals reported by Yunnan province who had either acute or chronic HBV infection and were from one of 20 ethnic minority populations: Achang, Bai, Brown, Tibetan, Dai, Deang, Dulong, Hani, Hui, Jingpo, Lahu, Yi, Lisu Miao, Naxi, Nu, Pumi, Wa, Yao, or Zhuang people. We sequenced the HBV DNA and determined the genotypes and subgenotypes of the isolated HBVs.

Impact of accentuated cut edges (ACE) technique on volatile and sensory profiles of Shiraz wines.

Varietal thiols are important wine aroma compounds that are generally less abundant in red wines. Accentuated cut edges (ACE), known for accelerating phenolic extraction, was applied to Shiraz winemaking and compared with conventional crushing (NOACE) to examine the effects on varietal thiol precursor extraction and thiol formation. Water addition to grape must and skin contact time (SCT) during fermentation were also assessed.

Chemical and Sensory Impacts of Accentuated Cut Edges (ACE) Grape Must Polyphenol Extraction Technique on Shiraz Wines.

Accentuated Cut Edges (ACE) is a recently developed grape must extraction technique, which mechanically breaks grape skins into small fragments but maintains seed integrity. This study was the first to elucidate the effect of ACE on Shiraz wine's basic chemical composition, colour, phenolic compounds, polysaccharides and sensory profiles. A further aim was to investigate any potential influence provided by ACE on the pre-fermentation water addition to must.

Potato Protein Fining of Phenolic Compounds in Red Wine: A Study of the Kinetics and the Impact of Wine Matrix Components and Physical Factors.

Producing wines within an acceptable range of astringency is important for quality and consumer acceptance. Astringency can be modified by fining during the winemaking process and the use of vegetable proteins (especially potato proteins) as fining agents has gained increasing interest due to consumers' requirements. The research presented was the first to investigate the effect of a potato protein dose on the kinetics of tannin and phenolic removal compared to gelatin for two unfined Cabernet Sauvignon wines.

A Ratiometric and Colorimetric Hemicyanine Fluorescent Probe for Detection of SO Derivatives and Its Applications in Bioimaging.

Based upon the intramolecular charge transfer (ICT) mechanism, a novel ratiometric fluorescent probe was developed to detect SO/HSO. The probe displayed both colorimetric and ratiometric responses toward SO/HSO. It displayed a quick response (within 60 s), good selectivity and high sensitivity (a detection limit of 28 nM) towards SO/HSO.

Dynamic characterization of wine astringency profiles using modified progressive profiling.

Wine astringency is important for quality and consumer acceptance. Perception of this mouthfeel is temporal and can be separated further into unique textural sub-qualities. Quantitative data on these astringent sub-qualities in wine however are poorly understood.

Investigation of the risk factors associated with the failure of hepatitis B vaccination of neonates in Yunnan province, China.

Objective: This study aimed to investigate HBsAg positive rates and risk factors of HBV infection among the children less than 15 years old in Yunnan province, a remote southwest part of mainland China.

Methods: Multi-stage sampling was used to randomly select study subjects from 9,360,000 individuals. Hepatitis B vaccine inoculation rate and HBsAg positive rate were investigated, and then propensity score and generalized linear mixed model (GLMMs) were applied to the case-control study.

Risk factors related to the failure of prevention of hepatitis B virus Mother-to-Child transmission in Yunnan, China.

Objective: To investigate the relationship between the failure of prevention of hepatitis B virus Mother-to-Child transmission and HBV serological pattern, viral load as well as HBV genotypes.

Methods: 2765 pairs of mother-infant matched samples were collected. These pregnant women were HBsAg positive and delivered at hospital from January 1st, 2011 to June 30th, 2011.

Risk factors associated with immunoprophylaxis failure against mother to child transmission of hepatitis B virus and hepatitis B vaccination status in Yunnan province, China.

Objective: To explore the risk factors associated with immunoprophylaxis failure against mother to child transmission of hepatitis B virus (HBV) and hepatitis B vaccination status in Yunnan province, China.

Methods: Multicenter cluster sampling was used to select pregnant women who were positive for hepatitis B surface antigen (HBsAg). HBV immunoprophylaxis was carried out for the newborns.

[Evaluation on the efficacy of prevention programs and relevant factors targeting mother-to-infant transmission on hepatitis B virus in Yunnan province].

Objective: To explore the efficacy of prevention programs and relevant factors targeting mother-to-infant transmission of HBV in Yunnan province.

Methods: In Yunnan province, we selected HBsAg positive pregnant women that delivered in hospital from January 1st through June 30th, 2011. Newborns of these pregnant women were under PMTCT (prevention of mother to child treatment) program and followed.

Application of gas chromatography-quadrupole-time-of-flight-mass spectrometry for post-target analysis of volatile compounds in Fructus Amomi.

A post-target analysis method based on gas chromatography coupled to a high-resolution quadrupole time-of-flight mass analyzer is applied for the investigation of volatile compounds in Fructus Amomi. A series of narrow window extracted ion chromatograms at selected characteristic ions were performed. Chromatographic peaks with the same retention time in different extracted ion chromatograms was used to screen out the candidate compound.

[Distribution of hepatitis B virus genotypes and serotypes in people who had a physical examination in Yunnan Province].

Objective: To know genotypes and serotypes of hepatitis B virus (HBV) detected from hepatitis B infected people in Yunnan Province.

Methods: Serum samples were collected from HBsAg carriers detected from people who had a physical examination at Yunnan Provincial Center for Disease Control and Prevention. The S genes of HBV were amplified by nested PCR and the PCR products were sequenced.

[Molecular identification of hepatitis B virus genotype I in Yunnan Province, the People's Republic of China].

Molecular typing was conducted according to the reported method for one HBsAg positive carrier who had a physical examination in Yunnan Province. The S gene of this HBV sample was amplified by nested PCR and the PCR products were directly sequenced. Blast searching was done on the Genbank database and the sequence were compared with the HBV reference sequences in database.

Effects of Antrodia camphorata on alcohol clearance and antifibrosis in livers of rats continuously fed alcohol.

Alcoholic fatty liver disease (AFLD) is the result of an excessive or chronic consumption of alcohol. Nine male Wistar rats per group were randomly assigned to one of the following drinking treatments: a 20% (w/w) alcohol solution (ALC); a 20% (w/w) alcohol solution cotreated with 0.25 g silymarin/kg BW/day; or a 20% (w/w) alcohol solution cotreated with 0.

Fruiting body of Niuchangchih (Antrodia camphorata) protects livers against chronic alcohol consumption damage.

An alcoholic fatty liver disease was induced by drinking water containing 20% (w/w) alcohol. Therapeutic groups were orally administrated dosages of 0.25 g silymarin/kg body weight (BW) and a low dosage of Niuchangchih (Antrodia camphorata) (0.